Cutter assembly

ABSTRACT

A cutter assembly comprising a cage support in which a cutter is rotatably mounted on a shaft, the shaft and support having surfaces which are mutually engageable, and/or arranged for receiving penetrating hardware, to restrain the shaft against rotation. The cage support carries on integral socket for replaceably securing a scraper.

United States Patent Inventors Williant n. Coski Mercer Island; William11. Hamilton, Seattle, both of, Wash. Appl. No. 825,654 Filed May 19,1969 Patented Aug. 24, 1971 Assignee Lawrence Manuhduring CompanySeattle, Wash.

CUTTEK ASSEMBLY 24 Claims, 6 Drawing gt.

US. Cl. 175/313, 175/364, 299/86 Int. CL E211) 9/08 Field of Search83/665, 666; 299/67, 68, 86; 308/82; 175/346, 347, 364, 313, 372

[56] References Cited UNITED STATES PATENTS 1,320,394 11/1919 Hughes175/227 1,661,715 3/1928 Carlson..... 175/347 X 1,670,092 5/1928 Bailey175/364 X 1,908,049 5/1933 Reed 175/313 1,915,527 6/1933 Hamakeret a1..175/372 X 2,187,037 1/1940 Kirkpatrick 308/82 2,310,584 2/1943 Kennedy1751346 3,216,513 11/1965 Robbins etal. 175/364X Primary Examiner-EmestR. Purser Attorneys-Car1 R. Horten, David W. Tibbott and Bernard J.

Murphy ABSTRACT: A cutter assembly comprising a cage support in which acutter is rotatably mounted on a shaft, the shaft and support havingsurfaces which are mutually engageable, and/or arranged for receivingpenetrating hardware, to restrain the shaft against rotation. The cagesupport carries on integral socket for replaceably securing a scraper.

PATENTED M82419?! 3501.207

SHEET 1 [IF 2 INVENTORS WILL/AM D. COS/(l WILL/AM H. HAM/L 7'0/V AGENTCUTTER ASSEMBLY This invention pertains to a cutter assembly comprisingmeans for supporting a shaft on which a cutter is rotatably mounted, andin particular to supporting means for a cutter and shaft whichfacilitates quick and simple cutter and shaft replacement.

In the prior art it is known to use a cage block which receives abearing support fastened thereto by means of four or more cap screws,the bearing support being bored through for receiving a shaft on which acutter is mounted. Additionally, retainer plates are disposed in thebearing support at either ends of the shaft. and secured with hardwareto retain the shaft in place against axial movement. This knownarrangement makes replacement of the cutter and shaft a laboriouslyinvolved process.

In addition, it is common in the prior art to provide a separatemounting support on the cutterhead, or whatever, to receive a scraper,the scraper being mounted adjacent to the cutter to clear a path inadvance thereof. Here too, additional hardware is involved for securingthe scraper in the support.

of the cutter and shaft. It is another object of this invention toprovide a cutter assembly comprising a scraper support integral withsupporting means for a cutter and shaft.

A feature of this invention, in one embodiment thereof, comprises theprovisioning of a cage-type support having a relieved area or cove'ofgiven shape in a wall thereof and a shaft having a complementaryrelieved surface, the cove and shaft complementary surfaces beingengageable to restrain the shaft against rotation relative to thesupport.

Further objects and features of this invention will become more apparentby reference to the following description taken in conjunction with theaccompanying figures in which:

FIG. 1A is an isometric projection of the cutter and shaft, andsupporting means therefor, which comprise the cutter assembly, accordingto the invention, in which the cutter is shown phantomed to facilitate aclear understanding of the shape of the cage-type support cage, andhardware and retainers deployed to retain the shaft are shown inexploded view at one shaft end;

FIG. 1B depicts an alternate arrangement of hardware for use in a cutterassembly such as that of the FIG. 1A embodimerit;

FIGS. 2 and 3 show, in isometric projections, portions of cutterassemblies, according to our invention, in which alterriate embodimentsof the novel means for mounting the shaft are illustrated; and

FIGS. 4 and 5, vertical illustrations having partial cross sec tions,present configurations of cutters employed in the cutter assembliesaccording to our invention.

As shown in FIG. 1 a cutter assembly comprises a sup port 12 of a cage"configuration which comprises oppositely disposed sidewalls l4 and 16which have arcuate relieved areas or.coves 18 for receiving a shaft 20.The shaft 20 is deployed for mounting a cutter and has terminal portions22 which haveflattened surfaces 24 provided for arresting the shaftagainst rotation. A pair of bars 26, which also have flattened surfaces28, are disposed across surfaces 24 to restrain theshaft. Bars 26eachhave a dowel extension 30 which is engaged with a borehole 32 formedin each of the walls 14 and 16. Additionally, bars 26 have boltholes 34formed therethrough which are in alignment with boltholes 36 formed inwalls '14 and 16 to receive mounting hardware. Also,each wall 14and 16has a nut hole 38 in which is disposed a round, or rod nut 40 which nuthas a tapped bolthole 42 therein. On assembly, with bars 26 in placeupon the terminal portions 22 of shaft 20, the boltholes 34 and 36 andthe tapped holes 42 are in alignment, and receive bolts 44 for securingthe bars 26 in place. Chordal shoulders 45 of shaft 20 have bars 26disposed next thereto.

A locking plate 46 is disposed between the head of the bolts 44 and bars26 so that the extending tangs 47, 47a of the locking plate may beturned against a flatted surface of the hex head of the bolt, and oneend of bar 26, respectively, to secure the bolt against loosening.

The coves 18 have first and second radial dimensions 48 and 50 whichaccordingly form therebetween a shoulder 52. The terminal ends ofportions 22 of shaft 20 abut the shoulder .52 to secure the shaft-endcutter against axial movement, and

the arcuate, radial surfaces 54 of portions 22 nestingly engage thefirst radial dimension 48 of cove 18.

Walls 14 and 16 are joined by a further wall 56 on the rear of which,i.e., rear meaning the surface of wall'56 which is external of theassembly, are formed converging tracks 58 and 60. Tracks 58 and 60comprise a tapered socket which frictionally receives and holds ascraper 62 for disposition in ad vance of the cutter 63. Each track 58and 60 is inclined from the vertical at a slight angle Z, and thescraper 62 has a complementary tapered configuration.

This embodiment of our cutter assembly just described greatlyfacilitates and simplifies replacement of cutter 63 together with shaft20, in that it only requires the removal of two bolts 44 to enable adisengagement of the cutter and shaft from the support 12. Yet, onassembly, the complementary linear surfaces 28 and 24 secure the shaftagainst rotation. Further, shoulder 52 constrains the shaft 20 againstaxial displacement. In other embodiments of our invention we teach theuse of complementary linear surfaces in the same manner to both securethe shaft against rotation, as well as axial displacement, and to enablequick and easy replacement of the shaft and cutter, as shown in FIG. 2for instance.

Altemately, a cutter assembly, such as that of assembly 10 of FIG. 1A,can deploy modified hardware-retaining components. Such a modificationis shown in FIG. 18 where a bar 26', similar to that of bar 26 in FIG.IA, is used. Bar 26' has a relieved land 27 formed thereon whichterminates, at one end, in a stop shoulder 29. Land 27 and shoulder 29are provisioned to receive a locking plate 46'. Upon assembly, bolt 44(FIG. 1A) is passed through the hole provisioned in plate 46', andboltholes 34 and 36 of bar 26 and walls l4 and 16 (FIG. 1A). The oneflatted end 31 of plate 46' abuts shoulder 29, and the other end 33 isturned up to engage a flatted portion of the head of bolt 44 after thebolt is fully torqued in place in rod nut 40.

In FIG. 2 a support 64 is indicated with a fragment of a sidewall 66which has a relieved area or cove 68 formed therein. Cove 68 receives aterminal portion 70 of a shaft 72. The terminal portion has flattedsurfaces 74 on opposite sides which nest with and engage flattedsurfaces 76 formed at either sides of the cove .68. Surfaces 76 areformed in the otherwise circular shaft 72 and extend perpendicularlyfrom chordal shoulders 78 which bear against shouldered surfaces 80presented at either side of cove 68. A pinhole 82 is formed to eitherside of cove 68, through'buttresses 84, and the ter minal portion 70 ofthe shaft 72 has a complementary pinhole 86. Accordingly, the pinholesare in alignment and receive a locking pin 88. In this embodiment of ourinvention the flatted surfaces 74 and 76 comprise complementary linearsurfaces which restrain the shaft against rotation, and shaft and cutterreplacement in this embodiment is very simply accomplished by removingpin 88 from the buttresses 84 and pinholes.

In a further embodiment of our invention, as shown in FIG. 3, a fragmentof a support 90 is presented as comprising a wall 92 which has a cove 94formed therein to receive the terminal portion 96 of a shaft 98. Abolthole 100 is formed in wall 92, and aligns with boltholes 102 and 104formed in terminal portion 96 and a pillow block cap 106, respectively.The pillow block cap 106 surmounts the terminal portion 96 of the shaft,and has an arcuate surface 107 which engages said portion. A rod-nut108, which has a tapped bore 110 therein, is carried in wall 92. A bolt112 is disposed through the bolt holes, and it engages rod nut 108, bothto secure the cap 106 to the wall 92, and to restrain the shaft 98against rotation. In addition surfaces 114 and 116, respectively, of thewall and cap are in abutting engagement to add further restraint againstrotation of the shaft.

The rod-nuts 40 and 108, shown in FIGs. l and 3, are provided to guardthe supports 12 and 90, respectively, against stripped-thread damage.Should it occur that bolts 44 and/or 112 are overtorquedor otherwiseoverstress the threads in rod-nuts 40 and/or 108-it is then onlynecessary to replace the rod-nuts.

In FIG. 4 there is more fully illustrated the cutter 63 which wasindicated only in phantom in FIG. 1. Cutter 63 has a row 118 of cuttingelements 120 and is mounted on shaft 20. Shaft has the prior-notedterminal portions 22 with the flatted portions 24 for engagement withthe bars 26. In this partial cross section it is shown that the cutter63 has a pair of spherical roller bearings 122 disposed therewithin tofacilitate its rotation relative to shaft 20. Cylindrical rollerbearings or ball bearings could be used in alternate embodiments of ourinvention, in place of spherical roller bearings 122, provided that suchroller bearings or ball bearings have adequate radial and thrust loadcapacity. Metal-to-metal face seals 124 protect the bearings against theintroduction of dirt and other foreign matter. A bearing retainer 126 isthreadably engaged with one end of the cutter shell 128 for positioningand securing the bearings in place. A tang 130 is deformed from theretainer, and disposed in a slot 132 provided therefor in cutter shell128. Finally, shaft 20 has a lube passageway 134 formed thereinextending axially to the center thereof where it is joined by radialpassageway 136. The external end of passageway 134 opens on a pipe plugbore 138. The passageways are provided for charging the bearing chamber139 of cutter 63 with lubricant after which the passageways are sealedby the implacement of a pipe plug (not shown) in bore 138.

Each seal 124 comprises a rotating metal face or annulus 125 and aresilient ring 127 which resiliently constrains the annulus against theinner race of bearing 122. Annulus 125 and ring 127 rotate in unisonwith shell 128, annulus 125 all the while sliding or rubbing against thebearing race.

In FIG. 5 we show an alternate cutter 63 usable at least, with theembodiment of FIG. 1in place of cutter 63-in which compliant seals 140are shown at either sides of bearings 122 for sealing thelubricant-charged bearing chamber 142.

Seals 140 are also of the rotating metal face type. Each comprises arotating annulus 141 resiliently constrained against the inner race ofbearing 122 by a resilient ring 143. Seal 140 rotates in unison with theshell 128, annulus 141 all the while sliding about the bearing race.

While we have described our invention in connection with specificembodiments thereof it is to be clearly understood that this is doneonly by way of example and not as a limitation to the scope of ourinvention as set forth in the objects thereof and in the appendedclaims.

We claim:

1. A cutter assembly, comprising:

a cutter shaft having a longitudinal axis; and means supporting saidshaft at least on one end of said shaft axis; wherein said supportingmeans comprises a cage-type support having oppositely disposed sidewallsjoined by a further wall;

said shaft has at least one given linear surface which lies transverseto said axis;

at least one of said sidewalls includes means having at least onecomplementarylinear surface in mating engagement with said given surfaceto restrain said shaft against rotation; and

said further wall includes means for replaceably and only frictionallymounting a scraper for clearing a path in advance of a cutter mounted tosaid shaft.

2. A cutter assembly, according to claim 1, wherein:

said one sidewall has a relieved area therein in which a portion of saidshaft is disposed.

3. A cutter assembly, according to claim 2, further including:

fastener means, in penetration of said one sidewall and said portionsecuring said portion, in said relieved area.

4. A cutter assembly, according to claim 3, wherein:

said fastening means comprise a pin.

5. A cutter assembly, according to claim 2, wherein:

said relieved area defines a cove extending into one lateral edge ofsaid one sidewall.

6. A cutter assembly, according to claim 5, wherein:

said cove is defined by rectilinear sides.

7. A cutter assembly, according to claim 6, wherein:

said shaft, excepting at least said portion, is of circular crosssection; and

said portion has parallel, flatted surfaces, extending perpendicularlyfrom adjacent chordal shoulders, which matingly engage said rectilinearsides.

8. A cutter assembly, according to claim 7, wherein:

said chordal shoulders abut said one sidewall.

9. A cutter assembly, according to claim 5, wherein:

said cove is defined by arcuate sides.

10. A cutter assembly, according to claim 9, wherein:

said arcuate sides each have a different radius which sides togetherdefine a semiannular, stepped shoulder therebetween; and

a terminal end of aid portion abuttingly engages said shoulder.

11. A cutter assembly, according to claim 10, wherein:

said shaft excepting at least said portion, is of circular crosssection; and

said portion has a flatted surface, extending perpendicularly from anadjacent chordal shoulder, and an arcuate, radial surface contiguouswith said flatted surface, which arcuate surface nestingly engages oneof said arcuate sides.

12. A cutter assembly, according to claim 11, wherein:

said complementary linear-surfaced means comprise retainer means infastened engagement with said one sidewall, and overlying said portionin restraining engagement with said flatted surface.

13. A cutter assembly, according to claim 12, wherein:

said retainer means comprises a bar having one end in penetration ofsaid one sidewall, and the other end thereof having a bolthole formedtherethrough, and includes a bolt in penetration of said boltholefastened in, and securing said bar to, said one sidewall.

14. A cutter assembly, according to claim 13, wherein:

said one sidewall carries a rod-nut therewithin with which said bolt isthreadedly engaged.

15. A cutter assembly, according to claim 9, wherein:

said complementary linear-surfaced means comprise retainer means infastened engagement with said one sidewall, and overlying said portion.

16. A cutter assembly, according to claim 15, wherein:

said shaft has a first, linear, borehole formed therethrough,

within said portion; and

said retainer means comprises a pillow-block-type cap having ashaft-engaging surface, and a second linear borehole formed therethroughin registry with said first borehole, and a bolt fastened in, andsecuring said cap to, said one sidewall and restraining said shaftagainst rotation.

17. A cutter assembly, according to claim 16, wherein:

said cap-bearing surfaces in abutting engagement with complementarysurfaces of said one sidewall which are cooperative with said bolt torestrain said shaft against rotation.

18. A cutter assembly, according to claim 1, wherein:

said mounting means comprises a socket defined by opposed and convergingtracks.

19. A cutter assembly, according to claim 1, further including:

cutter means carried by said shaft; and

means interposed between said shaft and said cutter means facilitatingrotation of the latter relative to the former.

20. A cutter assembly, according to claim 19, wherein:

metal-to-metal, face-type seals closing said chamber means againstforeign matter.

23. A cutter assembly, according to claim 21, further includingcompliant seals closing said chamber means against foreign matter.

24. A cutter assembly, according to claim 22, wherein:

said seals comprise resiliently mounted metal annuluses rotatably withsaid cutter means and slidably engaged with, and resiliently constrainedagainst races of said roller bearings.

1. A cutter assembly, comprising: a cutter shaft having a longitudinalaxis; and means supporting said shaft at least on one end of said shaftaxis; wherein said supporting means comprises a cage-type support havingoppositely disposed sidewalls joined by a further wall; said shaft hasat least one given linear surface which lies transverse to said axis; atleast one of said sidewalls includes means having at least onecomplementary linear surface in mating engagement with said givensurface to restrain said shaft against rotation; and said further wallincludes means for replaceably and only frictionally mounting a scraperfor clearing a path in advance of a cutter mounted to said shaft.
 2. Acutter assembly, according to claim 1, wherein: said one sidewall has arelieved area therein in which a portion of said shaft is disposed.
 3. Acutter assembly, according to claim 2, further including: fastenermeans, in penetration of said one sidewall and said portion securingsaid portion, in said relieved area.
 4. A cutter assembly, according toclaim 3, wherein: said fastening means comprise a pin.
 5. A cutterassembly, according to claim 2, wherein: said relieved area defines acove extending into one lateral edge of said one sidewall.
 6. A cutterassembly, according to claim 5, wherein: said cove is defined byrectilinear sides.
 7. A cutter assembly, according to claim 6, wherein:said shaft, excepting at least said portion, is of circular crosssection; and said portion has parallel, flatted surfaces, extendingperpendicularly from adjacent chordal shoulders, which matingly engagesaid rectilinear sides.
 8. A cutter assembly, according to claim 7,wherein: said chordal shoulders abut said one sidewall.
 9. A cutterassembly, according to claim 5, wherein: said cove is defined by arcuatesides.
 10. A cutter assembly, according to claim 9, wherein: saidarcuate sides each have a different radius which sides together define asemiannular, stepped shoulder therebetween; and a terminal end of aidportion abuttingly engages said shoulder.
 11. A cutter assembly,according to claim 10, wherein: said shaft excepting at least saidportion, is of circular cross section; and said portion has a flattedsurface, extending perpendicularly from an adjacent chordal shoulder,and an arcuate, radial surface contiguous with said flatted surface,which arcuate surface nestingly engages one of said arcuate sides.
 12. Acutter assembly, according to claim 11, wherein: said complementarylinear-surfaced means comprise retainer means in fastened engagementwith said one sidewall, and overlying said portion in restrainingengagement with said flatted surface.
 13. A cutter assembly, accordingto claim 12, wherein: said retainer means comprises a bar having one endin penetration of said one sidewall, and the other end thereof having abolthole formed therethrough, and includes a bolt in penetration of saidbolthole fastened in, and securing said bar to, said one sidewall.
 14. Acutter assembly, according to claim 13, wherein: said one sidewallcarries a rod-nut therewithin with which said bolt is threadedlyengaged.
 15. A cutter assembly, according to claim 9, wherein: saidcomplementary linear-surfaced means comprise retainer means in fastenedengagement with said one sidewaLl, and overlying said portion.
 16. Acutter assembly, according to claim 15, wherein: said shaft has a first,linear, borehole formed therethrough, within said portion; and saidretainer means comprises a pillow-block-type cap having a shaft-engagingsurface, and a second linear borehole formed therethrough in registrywith said first borehole, and a bolt fastened in, and securing said capto, said one sidewall and restraining said shaft against rotation.
 17. Acutter assembly, according to claim 16, wherein: said cap-bearingsurfaces in abutting engagement with complementary surfaces of said onesidewall which are cooperative with said bolt to restrain said shaftagainst rotation.
 18. A cutter assembly, according to claim 1, wherein:said mounting means comprises a socket defined by opposed and convergingtracks.
 19. A cutter assembly, according to claim 1, further including:cutter means carried by said shaft; and means interposed between saidshaft and said cutter means facilitating rotation of the latter relativeto the former.
 20. A cutter assembly, according to claim 19, wherein:said rotation-facilitating means comprise spherical roller bearings. 21.A cutter assembly, according to claim 20, wherein: said cutter meansinclude chamber means for accommodating said bearings; and said shafthas lubricant passageways formed therein, in communication with saidchamber means, for lubricant-charging of said chamber means.
 22. Acutter assembly, according to claim 21, further including:metal-to-metal, face-type seals closing said chamber means againstforeign matter.
 23. A cutter assembly, according to claim 21, furtherincluding compliant seals closing said chamber means against foreignmatter.
 24. A cutter assembly, according to claim 22, wherein: saidseals comprise resiliently mounted metal annuluses rotatably with saidcutter means and slidably engaged with, and resiliently constrainedagainst races of said roller bearings.